An e-commerce site with universal product pages and category pages, but also personalized recommendation sections

You can also use your React components to create interactive widgets e.g. allow a user to do searches or submit forms. Because Gatsby is just React, it’s easy to blend static and interactive/dynamic models of building web sites.

Client-only routes & user authentication

Often you want to create a site with client-only portions that are gated by authentication.

A classic example would be a site that has a landing page, various marketing pages, a login page, and then an app section for logged-in users. The logged-in section doesn’t need to be server rendered as all data will be loaded live from your API after the user logs in. So it makes sense to make this portion of your site client-only.

Gatsby uses React Router under the hood. You should use React Router to create client-only routes.

These routes will exist on the client only and will not correspond to index.html files in an app’s built assets. If you wish people to visit client routes directly, you’ll need to setup your server to handle these correctly.

To create client-only routes, you want to add code to your site’s gatsby-node.js like the following:

// Implement the Gatsby API “onCreatePage”. This is// called after every page is created.
exports.onCreatePage =async({ page, boundActionCreators })=>{const{ createPage }= boundActionCreators;// page.matchPath is a special key that's used for matching pages// only on the client.if(page.path.match(/^\/app/)){
page.matchPath ="/app/:path";// Update the page.createPage(page);}};